Stenotrophomonas maltophilia is a human opportunist pathogen, with an environmental origin. Members of the species are common inhabitants of water and soils, including rhizosphere. S. maltophilia can be a plant endosymbiont and is found in animals and washed foods. This Gram-negative bacterium has intrinsic resistance to various classes of antimicrobials. Within the S. maltophilia genome, genes encoding antibiotic inactivating enzymes, multidrug efflux pumps, and a quinolone resistance gene contribute to its reduced antibiotic susceptibility. Although a low virulence pathogen, S. maltophilia can cause various infections in susceptible patients. In addition, S. maltophilia isolates present important biotechnological properties, which can be carefully taken into consideration given the pathogenic potential of this microorganism. This research topic examines S. maltophilia from different perspectives, and it includes 11 articles: 1 commentary, 7 primary research articles, and 3 review articles.